1. Field of the Invention
The present invention relates to apparatus for removing slag from the surface of metal shapes by the application of a substantially horizontal force to the slag.
When burning equipment is used to cut metal into desired shapes, a slag is formed on the surface of the shapes with a buildup along the cut edges of the shape. Slag formed during plasma arc and oxyfuel burning is extremely adherent to the metal and its hardness is inconsistent. This slag is difficult and expensive to remove by conventional apparatus such as abrasive belts or grinding wheels because the belts and wheels wear rapidly and unevenly. Manual chipping is impractical for removing slag created by plasma arc and oxyfuel burning because of the adherence of the slag to the metal. It is important that the slag created by burning be removed rapidly so that an efficient continuous in-line operation is maintained.
2. Description of the Prior Art
Apparatus wherein metal shapes are carried beneath a grinding wheel or an abrasive belt to remove slag by abrasion are known in the prior art. When an abrasive belt is used, grooves are rapidly worn in the belt where the belt contacts the slag buildup, and, hence, the belt must be replaced after slag has been removed from only a small number of workpieces. Abrasive belts are expensive and the cost of frequently replacing belts is prohibitive. The use of grinding wheels is likewise expensive as the wheels tend to wear rapidly and unevenly. Manual chipping of slag from a workpiece is also known but is impractical because of the expense and time involved and because the varying consistency of the slag and the adherence of the slag to the metal cause the edges of the metal shape to break off which destroys the shape.
An example of apparatus wherein metal shapes are carried beneath a rotating abrasive wheel on a continuous belt to grind a surface of the shape is British Patent No. 1,339,266. The grinding wheel in the apparatus disclosed in this patent is vertically adjustable so that the amount of material removed may be controlled. As stated above, grinding machines of this type are impractical for removing slag created by burning since the wheel breaks down and must be replaced at frequent intervals.